Investigating the role of brainstem neuroinflammation in cardiorespiratory control in a rat model of recurrent epilepsy

研究脑干神经炎症在复发性癫痫大鼠模型心肺控制中的作用

• 批准号: 10676746
• 负责人: Wasif A Osmani
• 金额: $ 4.98万
• 依托单位: MEDICAL COLLEGE OF WISCONSIN
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-01 至 2025-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10676746
• 关键词: Address; Affect; Animal Model; Antiepileptic Agents; Apnea; Architecture; Astrocytes; BLR1 gene; Baroreflex; Bioinformatics; Biological Assay; Brain; Brain Stem; Brain region; Breathing; CCL2 gene; CXCL13 gene; Cause of Death; Cell Nucleus; Cells; Cessation of life; Chemoreceptors; Chronic; DNA Sequence Alteration; Data; Epilepsy; Event; Exons; Exposure to; Failure; Fellowship; Female; Functional disorder; Gene Expression; Gene Expression Profile; Generations; Genes; Glial Fibrillary Acidic Protein; Goals; Health; Heart Arrest; Heart Rate; Hippocampus; Human; IL1R1 gene; Impairment; Individual; Inflammatory; Inpatients; Interleukin-1; Intervention; Intractable Epilepsy; Knock-out; Knowledge; Lead; Life; Ligands; Mediating; Mediator; Medical; Microglia; Modeling; Molecular; Monitor; Morphology; Nerve Degeneration; Neurologic; Neuronal Dysfunction; Neurons; Nuclear RNA; Nucleus solitarius; PTGS2 gene; Pathologic; Pathway Analysis; Pathway interactions; Patients; Pattern; Peptide Hydrolases; Persons; Play; Potassium Channel; Prevention; Proteins; Protocols documentation; Publishing; Rattus; Recurrence; Respiratory physiology; Risk; Rodent Model; Role; Seizures; Serotonin; Signal Pathway; Signal Transduction; Small Nuclear RNA; System; Testing; Tissue-Specific Gene Expression; Tissues; Tonic - clonic seizures; audiogenic seizure; cell type; chemokine; chemokine receptor; cytokine; experience; experimental study; glial activation; high risk; human data; inward rectifier potassium channel; male; mortality; neural circuit; neural network; neuroinflammation; new therapeutic target; novel; patient population; pharmacologic; preBotzinger complex; prevent; raphe nuclei; receptor; receptor function; respiratory; sound; sudden unexpected death in epilepsy; transcriptome sequencing; transcriptomic profiling; transcriptomics; zinc finger nuclease

Abstract: Epilepsy is one of the most common neurological conditions in the world. Treatment with anti-epileptic drugs (AEDs) prevent recurrent seizures in ~70% of patients with epilepsy, but the remaining 30% of patients with refractory epilepsies continue to experience uncontrolled seizures. The negative consequences of repeated seizures include post-ictal cardiorespiratory suppression putting these patients at high risk of Sudden Unexpected Death in Epilepsy (SUDEP). Fundamental knowledge gaps exist in our understanding of how repeated seizures disrupt the vital cardiorespiratory control systems in the brain. A factor commonly identified in many neurological conditions including epilepsy is neuroinflammation, which supports beneficial functions in health but is dysregulated in epilepsy patients and animal models of seizure disorder. Key cells within the CNS mediating pathological neuroinflammation are resident microglia and astrocytes, which have also been shown to be dysfunctional in human epilepsy. However, it is not known what mechanistic role the glial-derived neuroinflammation plays in the impairment of cardiorespiratory control or increased SUDEP risk. Here, I hypothesize that repeated seizures lead to activation of neuroinflammation mediated by microglia within key brainstem regions controlling cardiorespiratory function causing a progressive decline in these vital functions. Published and preliminary data in our novel rat model with genetic mutations in a gene (kcnj16) encoding an inwardly-rectifying potassium ion channel (Kir5.1; SSkcnj16-/- rats) show that repeated sound-induced seizures (1/day for up to 10 days) lead to progressively more severe post-ictal cardiorespiratory suppression and unexpected mortality particularly in male rats. Through snRNA sequencing and bioinformatic pathway analyses of transcriptomic changes specifically within microglial cells in the medullary raphe (key breathing control region) identified significant predicted activation of IL-1ß signaling following repeated seizures, consistent with immunofluorescent brainstem tissue analyses. Here I propose two Specific Aims which: 1) characterize cell- specific transcriptomic shifts in gene expression within key cardiorespiratory control regions to identify key cells types and pathways mediating local neuroinflammation leading to neuronal dysfunction, and 2) functionally test the roles of microglia and IL-1 signaling in the brain in mediating the progressive cardiorespiratory suppression and/or unexpected seizure-induced mortality. Identifying neuroinflammatory signals/pathways induced by repeated seizures within distinct neural circuits in our novel rat model will enhance our understanding of the pathophysiological consequences of uncontrolled seizures in patients with refractory epilepsy, and hold the potential for identifying new therapeutic targets aimed at preventing seizure-induced cardiorespiratory dysfunction function and reduce SUDEP risk.

摘要：癫痫是世界上最常见的神经系统疾病之一。抗癫痫药物治疗 药物(AEDs)在~70%的癫痫患者中防止癫痫复发，但其余30%的患者 顽固性癫痫持续出现失控发作。重复的负面后果 癫痫发作包括发作后心肺抑制，使这些患者处于突然发作的高风险 癫痫的意外死亡(SUDEP)。基本的知识差距存在于我们对 反复发作会扰乱大脑中重要的心肺控制系统。一个常见的因素是 包括癫痫在内的许多神经疾病都是神经炎症，它支持在 健康，但在癫痫患者和癫痫障碍动物模型中调节失调。中枢神经系统内的关键细胞 介导病理性神经炎症的是驻留的小胶质细胞和星形胶质细胞，它们也已被证明 在人类癫痫中出现功能障碍。然而，目前还不知道神经胶质细胞衍生的机制是什么。 神经炎症在心肺控制功能受损或SUDEP风险增加中起作用。在这里，我 假设反复癫痫发作导致体内小胶质细胞介导的神经炎症激活 控制心肺功能的关键脑干区域导致这些重要的 功能。我们新的大鼠基因突变模型(Kcnj16)的已发表和初步数据 编码内向整流钾离子通道(Kir5.1；SSkcnj16-/-大鼠)表明，重复的声音诱导 癫痫发作(每天1次，最多10天)导致发作后逐渐严重的心肺抑制和 意外死亡，特别是雄性大鼠。通过SnRNA测序和生物信息途径分析 在延髓中缝(呼吸控制区的关键区域)的小胶质细胞内的转录改变 在反复癫痫发作后发现IL-1ç信号的显著预测激活，与 免疫荧光脑干组织分析。在这里，我提出了两个具体目标：1)描述细胞- 关键心肺控制区基因表达的特异性转录改变以识别关键细胞 介导局部神经炎导致神经元功能障碍的类型和途径；2)功能测试 脑内小胶质细胞和IL-1信号在介导进行性心肺抑制中的作用 和/或意外癫痫导致的死亡。识别神经炎性信号/通路 在我们的新的大鼠模型中，不同神经回路中的重复发作将增强我们对 难治性癫痫患者无控制发作的病理生理后果，并坚持 寻找旨在预防癫痫诱发的心肺疾病的新治疗靶点的可能性 功能障碍，降低SUDEP风险。